Gases containing significant concentrations of ammonia, acid gases and water vapor are difficult to process to separate the ammonia from the acid gases since treatment such as cooling or washing with water yields liquids containing substantial amounts of both ammonia and acid gases. Except at very low concentrations such liquids are very corrosive to both carbon steels and stainless steels. The processing of such liquids is complicated by the tendency of ammonia to combine with acid gases such as H.sub.2 S, CO.sub.2, and HCN in water.
Another problem associated with the processing of gases containing, ammonia, acid gases and condensable water vapor is that during contact with media used for the absorption of ammonia, such as ammonium phosphate solutions, the removal of ammonia and the condensation of water vapor will increase the partial pressures of the acid gases in the gas phase, which increase solubility of these components in the aqueous medium.
Mixtures of ammonia and acid gases are difficult to separate. Typical successful prior processes, for example, involve contacting coke oven gas with ammonium phosphate solution for the recovery of ammonia as shown in U.S. Pat. No. 3,024,090 and U.S. Pat. No. 3,186,795. It can be seen that in these processes, the concentration of ammonia and acid gases has been low, generally on the order of 1-2 precent for each, and the temperature of absorption has been generally low, say between 30.degree. and 60.degree. C.